arc: nsim: vpx5: fix SoC config issue which leads to cmake error

After recent nsim SoCs & boards reorganization the SOC_SERIES_*
config is missing for vpx5 SoC which leads to cmake errors
when building against nsim/nsim_vpx5 configuration.

Fix that and align soc series name in soc.yml

Signed-off-by: Evgeniy Paltsev <PaltsevEvgeniy@gmail.com>
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>